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A233171
Number of n X 5 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabeled 6-colorings with no clashing color pairs).
1
36, 8576, 2469888, 736362496, 221463445504, 66799223701504, 20170789919653888, 6093499625887498240, 1841146791439003287552, 556341623248212690206720, 168115390615337809829953536, 50801739257391729644354404352
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 480*a(n-1) -60416*a(n-2) +1966080*a(n-3) +22020096*a(n-4) -1845493760*a(n-5) +22548578304*a(n-6) -68719476736*a(n-7)
EXAMPLE
Some solutions for n=2
..0..1..2..4..2....0..1..5..2..4....0..1..2..5..3....0..1..2..4..0
..2..4..2..1..3....5..3..5..3..4....5..4..3..1..3....3..4..5..4..5
CROSSREFS
Column 5 of A233174.
Sequence in context: A203052 A054407 A268553 * A058466 A277603 A141475
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 05 2013
STATUS
approved